The present invention relates to a method of cloning a file system of a window web operating system by using a bitmap file, and more particularly to a method of cloning a file system by a bitmap file under the Microsoft Windows NT operating system.
Clone techniques are intensively used in mass production operations in computer production lines. These techniques commonly make the OS (Operating System) and Source File System Partition (hereinafter referred to as Source Partition) into a compressed file, then clone the compressed file onto every object disk, and then decompress the file, so as to produce object disks identical to the original Source Partition. These clone techniques greatly improve computer mass production efficiency. Further, conventional file clone techniques can also be applied to the preparation of a computer system copy for use in restoring the system when the computer system fails. Conventionally, file clone techniques adopt a regular procedure to compress file data in proper order. This operation speed is slow. Recently, a file clone technique has been developed, which, as shown in FIG. 1, compresses files rapidly without being in conformity with the order of the files. However, under Microsoft""s NT Operation System, this file clone technique is based on the File System. This technique compresses the content of the source partition subject to a Master File Table (hereinafter referred to as MFT), forming an Image File, and then decompresses the file after having been cloned to every object disk. During this process, the system inspects all information in the table of contents, finds out all files in the source partition and modifies the MFT in the object partition subject to the information on the size and partition condition included in the object disk. Because the NT File system (hereinafter referred to as NTFS) records file information in multiple addresses, a new partition cloned by means of the aforesaid file clone technique shows different file information at different addresses when the size of the source partition and the size of the object disk are different. This difference destroys the stability and unity of the system, preventing the file clone operation from proceeding, or even causing the partition to crash. Furthermore, the operation procedure of this file clone technique is complicated and slow, and weak in system protection.
The present invention has been accomplished to provide a file system clone technique, which eliminates the aforesaid drawbacks. The file system clone technique of the invention is to clone data but not the file. Therefore, it is not necessary to re-build the MFT in the object partition, so that the safety and unity of the system are ensured. The method of the present invention greatly increases file clone speed. The advantages of the present invention become more significant when the size of the source partition and the size of the object disk are different. According to one aspect of the present invention, the file system cloning method uses a bitmap file to clone the NT file system. During the data cloning process, few files are changed, and it is not necessary to rebuild the object partition MFT. Further, data access is directly made through the file system. Therefore, the file system cloning speed is high. According to another aspect of the present invention, the file system cloning method does not need to re-construct object partition MFT. Therefore, the procedure does not modify file recording information in the partition, and the safety and unity of NT file system are ensured. According to still another aspect of the present invention, the operation procedure of the file system cloning method of the present invention is simple, and a user can easily complete the clone of a NT file system without knowing the system internal structure.